Solutions to PCB Laminate Problem

Dated：2017-12-15 Popularity：1217

You may face some of the most common PCB laminate problems in your project, and here are solutions to them for your reference.

Have a reasonable directionDirections for input/output, AC/DC, strong/weak signal, high frequency/low frequency, high pressure/low pressure, etc. should be linear or separation, not blend with each other so as to prevent mutual interference. The best way is to design like a straight line though generally it is not easy to achieve. The most unfavorable direction is annular, but fortunately it can improve the isolation. PCB design requirements for DC, small signal and low voltage can be lower.

Choose a good groundingNormally, a good ground plays an important role in PCB function. In reality, some rules like the multiple groundings of the forward amplifier should be combined and then connected to the mains should try to be followed even various restrictions are difficult to fully handle.

Reasonable arrangement of power filter or decoupling capacitorIn general, only a few power filters or decoupling capacitors are shown in the schematic, but no indication is given for where they should be connected. In fact, these capacitors are designed for switching devices or other components that need to be filtered or decoupled. The layout of these capacitors should be as close as possible to these components. Interestingly, when the power filter or decoupling capacitor layout is reasonable, the problem of grounding will be less obvious.

Accurate Line LayoutIf condition permits, use wide lines rather than fine ones; high pressure and high frequency lines should be smooth, no sharp chamfering, no right angles at the corner. Ground should be wide, it is best to use a large area of copper, which can largely reduce the grounding problem.

Although some problems occur in the post-production, it may be caused by the imperfect PCB design. For example: 1. Too many through holes may be bad for sinking copper process, so the design should minimize the holes. 2. The density of parallel lines density is too large may easily cause defective soldering, so the line density should be determined by the level of soldering process. 3. The size of pad or wire hole is too small, or pad size and hole size with improper fit. The former is unfavorable to manual drilling, the latter is disadvantageous to CNC drilling. 4. Uneven corrosion is easily caused when the wire is too thin and the large un-wiring area has no copper. Therefore, the role of copper is to increase the ground area and improve anti-interference function.